1) includes "no reply".
Source： JARC, Report on Elderly Migration Survey in Sapporo City.
Those findings described above imply that the inmigration is larger than the outmigration in the prefecture with younger age structure, while the outmigration is larger than the inmigration with the prefecture with older age structure. In particular, the differences between both migartions are very large at the young adult ages. From those implications mentioned above, it can be explained that the serious aging phenomena in remote rural areas such as Shimane, Kochi, Kagoshima and Yamagata, etc. or in the central part of a large city or a metropolitan area such as Tokyo, Osaka or Nagoya were brought by heavy exodus of young adult population to urban or metropolitan prefectures or to the adjacent suburban areas.
In addition, another aspect of migration with relation to population aging should not be neglected. Observing precisely Figure 8, it can be known that the rates of both inmigration and outmigration declines sharply after the young adult ages but they tend to increase after the ages of 55-59 or around. Such tendency has been recognized throughout the nation since 1980 (Otomo, 1992). Particularly, it is distinguishable for a large city or for a metropolitan area such as Tokyo, Osaka or Nagoya. Such relatively high mobility of the elderly people may be explained mainly by the reasons of reunion of the elderly from a remote rural area invited to reside together with his or her family or of being taken care in a nursery home or a hospital, from the findings derived from the returns of the surveys taken by JARC (1991, 1992, 1993, 1994, 1995, 1996 and 1997). Table 8 presents the main reasons of the elderly migration derived from the returns of the recent survey by JARC (1996) in Chiba-city, one of the leading suburban cities within Tokyo metropolitan area.
